We present the synthesis and photophysical electroluminescent properties for a series of platinum(II) alpha-diimine bis(arylacetylide) complexes. The molecular structures five derivatives have been elucidated by X-ray crystallography. Intermolecular pi-pi interactions (between aromatic diimine phenylacetylide moieties) are apparent in crystal lattices two these. All bis(phenylacetylide) exhibit intense triplet metal-to-ligand charge transfer (MLCT) photoluminescence solid state fluid...

The capabilities of readily prepared and sublimable Pt(II) Schiff base triplet emitters as OLED dopants have been examined; maximum luminous power efficiencies luminance 31 cd A−1, 14 lm W−1, 23,000 m−2, respectively, white EL (CIE: 0.33, 0.35) by simultaneous host/dopant emission, achieved.

Efficient red electroluminescence from the excimer or oligomer of neutral phosphorescent bis(pyrrole)-diimine Pt(II) complex has been achieved with maximum external quantum efficiency, luminous power efficiency and brightness 6.5%, 9.0 cd A(-1), 4.0 lm W(-1) 11 100 m(-2), respectively.

We present an examination of the structural and photophysical characteristics [Pt(N(2)O(2))] complexes bearing bis(phenoxy)diimine auxiliaries (diimine=4,7-Ph(2)phen (1) 4,4'-tBu(2)bpy (2)) that are tetradentate relatives quinolinolato (q) ligand. These neutral derivatives display high thermal stability (>400 degrees C in N(2)). While crystal lattice 1 consists (head-to-tail)-interacting dimers, molecules 2 arranged into infinitely stacked planar sheets with possible pi-pi interactions but...

Osmium(II) complexes containing N-heterocyclic carbene (NHC)-based pincer ligand 1,3-bis(1-methylimidazolin-2-ylidene)phenyl anion (C(1)^C^C(1)) or 1,3-bis(3-methylbenzimidazolin-2-ylidene)phenyl (C(2)^C^C(2)) and aromatic diimine (2,2'-bipyridine (bpy), 1,10-phenanthroline (phen), 4,4'-diphenyl-2,2'-bipyridine (Ph(2)bpy)) in the form of [Os(C^C^C)(N^N)(CO)](+) have been prepared. Crystal structures for these show that Os-C(NHC) bonds are essentially single (Os-C(NHC) distances =...

Ruthenium(II) and osmium(II) complexes [M(C^N^C)(N^N)L](n+) (L = Cl(-), n 1; L CH3CN, t-BuNC, 2) containing a neutral tridentate N-heterocyclic carbene (NHC)-based pincer ligand, either 2,6-bis(1-butylimidazol-2-ylidene)pyridine (C(1)^N^C(1)) or 2,6-bis(3-butylbenzimidazol-2-ylidene)pyridine (C(2)^N^C(2)), 2,2'-bipyridine-type aromatic diimine have been prepared. Investigations into the effects of varying M (Ru Os), C^N^C, N^N, on structural, electrochemical, absorption, emission...

Reaction of [M(L-L)Cl(2)] [M = Pd, Pt; L-L 4,4'-di-tert-butyl-2,2'-bipyridine ((t)Bu(2)bpy), 4,4'-dimethylcarboxylate-2,2'-bipyridine ((CO(2)Me)(2)bpy), bis(diphenylphosphino)methane (dppm)] with Na(2)S in refluxing methanol afforded [M(3)((t)Bu(2)bpy)(3)(mu(3)-S)(2)](2+) Pd (1a), Pt (2a)], [M(3)((CO(2)Me)(2)bpy)(3)(mu(3)-S)(2)](2+) (1b), (2b)], and [Pt(3)(dppm)(3)(mu(3)-S)(2)](2+) (3) as perchlorate salts. X-ray crystal analysis revealed that 1a, 1b, 2a, 3 have triangular M(3)S(2) core...

The synthesis and photophysical properties of the robust Pt(II) emitters [(O∧N∧N)PtX] (HO∧N∧N = 6-(2-hydroxyphenyl)-2,2'-bipyridine its derivatives; X Cl, Br, I, or −C⋮C−Ph) are reported. Yellow electroluminescent devices based on these materials display a low turn-on voltage (1 cd m-2 at 4 V) high luminance (37000 m-2). Complex 2e, [(FtBu2O∧N∧N)PtCl], has highest thermal stability gave best OLED.

Abstract To probe the possibility that carbodicarbenes (CDCs) are redox active ligands, all four members of series [Fe( 1 ) 2 ] n + ( =2–5) were synthesized, where is a neutral tridentate CDC. Through combination spectroscopy and DFT calculations, electronic structure pentacation shown to be [Fe III .+ 5+ S = ). That 4+ more ambiguous, but it has significant contributions from open‐shell singlet )( )] =0). The observed spin states derive antiferromagnetic coupling their constituent low‐spin...

Abstract Metallafuran complexes with a fused five‐membered phosphonium ring were synthesized from reactions between terminal ynones HC≡C(C=O)R and cis ‐[Ru/Os(dppm) 2 Cl ] (dppm=1,1‐bis(diphenylphosphino)methane). A metal–vinylidene‐involving pathway was found to be an energetically feasible formation mechanism for these complexes. These phosphonium‐containing metallafurans, like many phosphonium‐functionalized drugs, have the ability induce mitochondrial dysfunction. They also exhibit...

Arenes are abundantly occurring molecules of significant interest as versatile starting materials in organic reactions. Typically, oxidation arenes yields planar such phenols and quinones. However, several iron dependent oxygenases can disrupt the aromaticity through introduce C(sp3)‐O stereogenic centers, resulting precious enantioenriched epoxide or diol products. Emulating this enzymatic behavior with synthetic catalysts has met little success until now. Herein we describe a catalytic...

Arenes are abundantly occurring molecules of significant interest as versatile starting materials in organic reactions. Typically, oxidation arenes yields planar such phenols and quinones. However, several iron dependent oxygenases can disrupt the aromaticity through introduce C(sp3)‐O stereogenic centers, resulting precious enantioenriched epoxide or diol products. Emulating this enzymatic behavior with synthetic catalysts has met little success until now. Herein we describe a catalytic...

An insertion reaction of nitrosonium ion (NO+) into the metal−carbon bond cyclometalated ruthenium(II) complexes is prepared with experimental evidence supporting a bimolecular direct NO+ (i.e., M−R + → [M−N(═O)−R]+) but not an intramolecular migratory R−M−(NO) L L−M−N(═O)R) as mechanism. Theoretical calculations suggest that M−C may be rationalized frontier orbital interaction between [Ru−aryl]-dominated HOMO Ru(II) and LUMO NO+.

Ruthenium complexes containing 2-(2-nitrosoaryl)pyridine (ON∧N) and tetradentate thioether 1,4,8,11-tetrathiacyclotetradecane ([14]aneS4), [Ru(ON∧N)([14]aneS4)]2+ [ON∧N = 2-(2-nitrosophenyl)pyridine (2a), 10-nitrosobenzo[h]quinoline (2b), 2-(2-nitroso-4-methylphenyl)pyridine, (2c), 2-(2-nitrosophenyl)-5-(trifluoromethyl)pyridine (2d)] analogues with the 1,4,7-trithiacyclononane ([9]aneS3)/tert-butylisocyanide ligand set, [Ru(ON∧N)([9]aneS3)(C≡NtBu)]2+ (4a 4b), have been prepared by insertion...

Redox-active ligands: Structural, spectroscopic, and theoretical studies of ruthenium(II) complexes bearing 2-(2-nitrosoaryl)pyridine ligands their reduced analogues reveals the redox noninnocence (see scheme). As a service to our authors readers, this journal provides supporting information supplied by authors. Such materials are peer reviewed may be re-organized for online delivery, but not copy-edited or typeset. Technical support issues arising from (other than missing files) should...

A series of neutral platinum(II) complexes with substituted 8-hydroxyquinoline ligands for use in organic electroluminescent devices have been prepared. These give deep-red to near-infrared phosphorescence λmax,peak from 650to695nm and λmax,shoulder 705to755nm. High-performance light-emitting are obtained using these bis(8-hydroxyquinolato) as a emitter maximum external quantum efficiency, luminous turn-on voltage 1.7%, 0.32cd∕A, 3.2V, respectively.

The <italic>N</italic>,<italic>N</italic>′-coordinated 1,2-dinitrosoarenes represent a new class of redox-active bidentate ligand.

Abstract The tert ‐butyl group is a common aliphatic motif extensively employed to implement steric congestion and conformational rigidity in organic organometallic molecules. Because of the combination high bond dissociation energy (~100 kcal mol −1 ) limited accessibility, absence directing groups, neither radical nor approaches are effective for chemical modification C−H bonds. Herein we overcome these limits by employing highly electrophilic manganese catalyst, [Mn( CF3 bpeb)(OTf) 2 ],...

Ruthenium(II)−chloride, −cyanide, and −phenylacetylide complexes bearing aromatic diimine (2,2′-bipyridine (bpy), 4,4′-dimethyl-2,2′-bipyridine (Me2bpy), or dipyrido-[3,2-f:2′,3′-h]-quinoxaline (dpq)) cyclic tridentate thioether 1,4,7-trithiacyclononane ([9]aneS3) have been prepared. The crystal structures of [Ru([9]aneS3)(bpy)(C≡N)](PF6) [Ru([9]aneS3)(diimine)(C≡CPh)](PF6) (diimine = bpy Me2bpy) reveal Ru−C distances 2.024(4) 2.030(3)−2.038(2) Å, respectively. oxidation waves for the are...

The two series of ruthenium-indolizinone complexes prepared by Ru-mediated cyclization pyridine-tethered alkynes represent the first examples metalated indolizinone complexes. Joint experimental-theoretical investigation suggests an unconventional 5-endo-dig pathway as their formation mechanism. They also exhibit moderate cytotoxicity against several human cancer cell lines.

Carbodicarbenes (CDCs) possess two lone pairs of electrons on their central carbone C atom (Ccarbone). Coordination to a transition metal via σ bond leaves one pair with appropriate symmetry for π donation the metal. However, high energy latter also renders CDC ligand potentially redox-active. Herein, we explore these alternatives in redox series [Cr(L)2]n+ and [Co(L)2]n+ (n = 2–5), where L is tridentate comprised flanking pyridine donors. To this end, all members both were synthesized...

In addition to oxometal [M(n+)[double bond, length as m-dash]O] and imidometal m-dash]NR] units, transient metal-iodosylarene [M((n-2)+)-O[double m-dash]IPh] metal-iminoiodane [M((n-2)+)-N(R)[double adducts are often invoked a possible "second oxidant" responsible for the oxo imido group transfer reactivity. Although few have been recently isolated and/or spectroscopically characterized, remained elusive. Herein, we provide UV-Vis, EPR, NMR, XAS DFT evidence supporting formation of complex 2...

The tert-butyl group is a common aliphatic motif extensively employed to implement steric congestion and conformational rigidity in organic organometallic molecules. Because of the combination high bond dissociation energy (~ 100 kcal mol-1) limited accessibility, absence directing groups, neither radical nor approaches are effective for chemical modification CH bonds. Herein we overcome these limits by employing an electron-poor manganese catalyst that operates strong hydrogen donor solvent...